Analog-to-digital signal conversion is useful for many signal processing applications, for example, interfacing with a photodiode sensor in a computed tomography (CT) imaging scanner.
Lyden et al. U.S. Pat. No. 7,136,005, entitled ACCURATE LOW NOISE ANALOG TO DIGITAL CONVERTER SYSTEM describes an analog-to-digital converter system that includes an integrator circuit front-end to an analog-to-digital converter circuit. An integration capacitor of the integrator circuit is reset in response to one or more comparators coupled to the output of the integrator detecting that the integrator output voltage is about to leave a designated output voltage range of the integrator circuit.
DeGeronimo U.S. Pat. No. 8,260,565, entitled HIGH DYNAMIC RANGE CHARGE MEASUREMENTS mentions a charge amplifier for use in radiation sensing including selectively diverting charge.
G. Mazza et al. “A 64-channel wide dynamic range charge measurement ASIC for strip and pixel ionization detectors,” Nuclear Science Symposium Conference Record, 2004 IEEE, p. 964-968, mentions a charge balancing integration technique.
G. C. Bonazzola et al. “A VLSI circuit for charge measurement of a strip ionization chamber,” Nuclear Instrumentation and Methods in Physics Research A 409 (1998), p. 336-338, mentions a charge transfer technique in an instrument to measure the beam intensity in hadron therapy cancer treatments.